A key problem with the argument over Darwinian evolution (evolution by natural selection acting on random mutations) is that so few actual examples of speciation (new species forming) have ever been observed that we really have no way of knowing for sure whether Darwin had the right idea.
I suspect that explains precisely why acceptance of Darwinism is so often treated as some kind of loyalty test for support for science in general.
That is, the Darwinist is taking a great deal on faith. And those Darwinists who also happen to be fanatics by temperament behave just as other fanatics do when they think they have found certainty: They go about like bulls looking for a fight - demanding that you too, brudder, better get saved. Otherwise, you face udder damnation …
As Jonathan Wells noted in his controversial Politically Incorrect Guide to Darwinism and Intelligent Design,
So except for polyploidy in plants, which is not what Darwin’s theory needs, there are no observed instances of the origin of species. As evolutionary biologists Lynn Margulis and Dorion Sagan wrote in 2002: “Speciation, whether in the remote Galapagos, in the laboratory cages of the drosophilosophers, or in the crowded sediments of the paleontologists, still has never been directly traced.” Evolution’s smoking gun is still missing.
– Jonathan Wells, Politically Incorrect Guide to Darwinism and Intelligent Design , p. 55, quoting Lynn Margulis and Dorion Sagan, Acquiring Genomes: A Theory of the Origin of Species (New York: Basic Books, p. 32)
In fairness to the fanatical Darwinist, unlike the Islamic extremist, he is only trying to separate doubters from their careers, not their heads.
That said, why not insist that at least one thousand obvious examples of speciation in animals – where we have a lot of information about what happened - be accumulated and studied, so that we have a study population to work with, to assess various theories of the origin of species?
 If we can’t find that within the next century, we need to assess just what role Darwinism is playing in science or society, because shedding light cannot really be the role.